We all know that ten-year-olds are too young to drive. But how old is too old to drive? We have formal age minimums in every state, but no formal age maximums.

Should there be?

The recent deadly accident involving an apparently confused 86-year-old man who lost control of his car and plowed into an open-air farmer's market in Santa Monica, Calif., killing ten and wounding more than 40, has rekindled the debate. If it’s reasonable to restrict access to motor vehicles based upon youth and immaturity, shouldn’t similar logic apply to advancing age and diminishing capacity?

The data and the tragedy

Accident data reflect that older drivers (especially those over 70) have a significantly higher risk of being involved in automobile accidents — especially single vehicle accidents that result from inadvertence, distraction, “falling asleep” behind the wheel, and so on. Nighttime driving is especially risky for older drivers, whose eyes are more affected by glare.

Unlike teens and young males under age 35, the cause of most accidents involving elderly drivers is not willfull recklessness but the declining physical and mental faculties associated with aging — and in the worst cases, a refusal to acknowledge them, and “self-police” by limiting driving, or foregoing driving altogether.

This appears to be what happened in Santa Monica, where 86-year-old Russell Weller drove his Buick at speed down a street that had been closed to motor vehicle traffic, and hit the gas instead of the brake when he realized his error.

“I think what we’re going to find is we have an 86-year-old driver that may not have been as competent as he needed to be to drive,” Santa Monica Police Chief James T. Butts Jr. told Good Morning America.

Weller probably should not have been on the road at all that day. While he had a valid driver’s license and had passed a visual and written exam in 2000, reports indicate he had recently crashed into his own garage on two occasions and was almost certainly an accident waiting to happen. Or worse: one that could have been prevented by more thorough screenings and tighter licensing procedures.

Stricter licensing the answer?

The problem in California, as in many states, is that drivers licensing and testing requirements are inadequate, and not just for older drivers. A cursory written test — mostly consisting of technical arcana such as how many feet one should stop behind a stopped school bus — plus an “eye chart” visual screening, followed by a ten-minute “drive around the cones” road test in the DMV parking lot are often all that is required. Once a first-time driver has passed the parking lot “road test,” few states ever again require a motorist to demonstrate actual proficiency behind the wheel to renew his or her license. (In another notorious case in Santa Monica, a teen was struck and killed by a 96-year-old driver who had not taken a road test since 1918.)

Only a few states test peripheral vision — critical to one’s field of view and to noticing merging traffic — or screen for adequate night vision among older drivers. None require the more substantial “on-road” road tests common in many European countries, where a person seeking a driver’s license must demonstrate competence on actual roads, in actual traffic, and not merely negotiate a couple of pylons in a parking lot at five mph.

If we want safer roads, such tests should be required of all drivers — the elderly included. A thorough road test at time of license issue or renewal would go a long way toward getting marginal drivers off the road, if only by making them confront their poor (or declining) driving skills. Such broad-based road tests would also have the virtue of not singling out the elderly; all drivers would have to successfully pass in order to get or renew their operator’s permit. No one could claim “discrimination,” or bias against the elderly. An 86-year-old who shows he’s still got what it takes to safely drive on public roads could keep right on driving — and just as easily, a 25-year-old who shows he hasn’t got what it takes could be taken off the roads until he

proves he can safely handle the responsibility of operating a motor vehicle.

Drivers over 65, when vision problems and other age-related issues become more common, should also have to pass more frequent (say, every two years up to age 75; then every year after that) visual screenings, including tests of peripheral vision.

There can be no reasonable objection to stricter licensing and testing requirements, since public safety is at issue and other drivers have every right to expect that the person in the next lane has demonstrated a certain basic level of competence behind the wheel. “Bias against the elderly” — or the young — doesn’t enter into it. You pass, you drive. You fail, you walk.